Alert archive / Alabama / Tornado Watches in 2004

Tornado Watch 129

April 29, 20044 states

The Storm Prediction Center issued this tornado watch at Apr 29, 2004, 8:55 PM CDT for 4 states. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Apr 29, 2004, 8:55 PM CDT (01:55 UTC)
Expired
Apr 30, 2004, 2:00 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
All 30 counties

Baldwin County, AL, Coffee County, AL, Covington County, AL, Dale County, AL, Escambia County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Mobile County, AL, Bay County, FL, Calhoun County, FL, Escambia County, FL, Holmes County, FL, Jackson County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Washington County, FL, Jefferson Parish, LA, Orleans Parish, LA, Plaquemines Parish, LA, Saint Bernard Parish, LA, Saint Tammany Parish, LA, Washington Parish, LA, George County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Pearl River County, MS, Stone County, MS

The radar

The Mobile radar (KMOB), 22 km from the middle of the area, began a volume at 01:54 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Warnings issued inside it

2 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 29, 9:14 PM CDTSevere Thunderstorm WarningTAEHolmes, Walton46 min
Apr 29, 9:44 PM CDTTornado WarningTAEHolmes, Washington31 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 1.9 hours before the alert went out and 149 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Slidell Radar S, LA at 00:00Z on 2004-04-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1025 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Slidell Radar S, LA at 00:00Z on 2004-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 73 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1025 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
490 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
73 m²/s²
0-3 km storm-relative helicity
128 m²/s²
Significant tornado parameter
0.5
Supercell composite
3.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS20 KWNS 300154
SEL9  
SPC WW 300155
ALZ000-FLZ000-LAZ000-MSZ000-CWZ000-300700-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 129
NWS STORM PREDICTION CENTER NORMAN OK
855 PM CDT THU APR 29 2004

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       SOUTHERN ALABAMA
       THE WESTERN FLORIDA PANHANDLE
       SOUTHEAST LOUISIANA
       SOUTHERN MISSISSIPPI
       COASTAL WATERS

EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 855 PM UNTIL
200 AM CDT.

TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 65 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 60 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 65 MILES NORTHWEST OF BOOTHVILLE LOUISIANA TO
40 MILES SOUTH SOUTHEAST OF DOTHAN ALABAMA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 126. WATCH NUMBER 126 WILL NOT BE IN EFFECT AFTER 855
PM CDT. CONTINUE...WW 125...WW 127...WW 128...

DISCUSSION...THREAT EXPECTED TO PERSIST FOR SUPERCELLS ALONG DIFFUSE
WARM FRONT LIFTING SLOWLY N ACROSS CNTRL/ERN GULF CST. INFLUX OF
RICH BOUNDARY LAYER MOISTURE...COUPLED WITH ENHANCED LOW LEVEL SSELY
JET ASSOCIATED WITH UPPER IMPULSE LIFTING NE ACROSS W TN...WILL
MAINTAIN FAVORABLE SHEAR PROFILES FOR ROTATING STORMS AND ISOLATED
TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 55 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 25030.


...CORFIDI

305,0900 313,0851 295,0851 290,0900

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 29, 7:51 PM CDTMesoscale DiscussionSPCBaldwin, Mobile, Monroe54 min
Apr 29, 9:25 PM CDTTornado WatchSPCColbert, Franklin, Lauderdale5 hr
Apr 29, 11:09 PM CDTMesoscale DiscussionSPCBaldwin, Coffee, Covington, Dale, Escambia, Geneva and 3 more96 min
Apr 29, 11:41 PM CDTMesoscale DiscussionSPCColbert, Franklin, Lauderdale64 min
Apr 30, 1:21 AM CDTMesoscale DiscussionSPCBaldwin, Coffee, Covington, Dale, Escambia, Geneva and 3 more24 min
Apr 30, 12:20 PM CDTMesoscale DiscussionSPCAlachua, Bradford, Clay, Duval, Flagler, Marion and 3 more2 hr
Apr 29, 8:58 PM CDTMesoscale DiscussionSPCAttala, Calhoun, Carroll, Chickasaw, Choctaw, Clarke and 28 more62 min

Nearby

Tornado Watches in Alabama, 2004Tornado Watches in Florida, 2004Tornado Watches in Louisiana, 2004Every tornado watch in 2004

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.